[PATCH] Use malloca instead alloca

[Florian Weimer]

On 01/08/2013 09:41 PM, Ondřej Bílka wrote:

> One technical issue is if we want to use STACKINFO_BP_DEF. It would make
> getting base pointer more portable but must be added to each function
> that uses __libc_use_alloca.

I'm interested in extending GCC to provide a better alloca, including 
one that can fail.  Parts of the split stacks support might reusable for 
obtaining the stack boundary.

I'm a bit skeptical about the whole alloca-if-we-have-room concept.  We 
must make sure that we keep sufficient stack space for further 
operation.  But I'm not sure how to determine the magic number of bytes 
to reserve.

-- 
Florian Weimer / Red Hat Product Security Team